The present invention relates to a pulse-controlled analog flip-flop, that is, a circuit having an output state which is one or the other of two voltage states and is controlled by a series of pulses, one or several pulses switching the flip-flop from a first state to a second state and an additional pulse making the flip-flop return from the second state to the first state.
Such a flip-flop can, for example, be used to control the gate of a MOS transistor, the first state corresponding to a voltage level adapted to turn on this MOS transistor and the other state corresponding to a voltage level adapted to turn off (make non-conductive) the MOS transistor.
An object of the present invention is to provide such a flip-flop which is of particularly simple structure.
Another object of the present invention is to provide such a flip-flop capable of providing high voltage levels.
Another object of the present invention is to provide such a flip-flop which is controllable either by a succession of positive pulses or by a succession of negative pulses.
Another object of the present invention is to provide such a flip-flop which can be simply modified to provide a positive or negative output voltage level.
To achieve these objects as well as others, the present invention provides a pulse-controlled analog flip-flop including a charge means; a charge storage means connected to the charge means; a means for detecting the voltage across the storage means; and a means for discharging the storage means when the detection means has detected that the voltage across the storage means has reached a predetermined threshold.
According to an embodiment of the present invention, the storage means includes a capacitor.
According to an embodiment of the present invention, the discharge means includes a thyristor.
According to an embodiment of the present invention, the detection means includes a Zener diode.
According to an embodiment of the present invention, the charge means includes a capacitor in series with a first diode between a first input terminal and a first terminal of the storage means, and a second diode connected between the connection point of said capacitor and of the first diode and a second supply terminal connected to the second terminal of the storage means.
According to an embodiment of the present invention, the analog flip-flop includes two input terminals; two output terminals; a first storage capacitor connected to the output terminals; a charge circuit, connected between the input terminals and the first capacitor, including a second capacitor connected to an input terminal in series with a first diode connected to the first terminal of the first capacitor, and a second diode connected between the connection point of the second capacitor and of the first diode and the second terminal of the first capacitor, and connected to the second input terminal; a thyristor connected across the capacitor; and a Zener diode connected between the thyristor gate and a terminal representative of the voltage across the capacitor.
According to an embodiment of the present invention, the Zener diode is connected to the connection point between the second capacitor and the first diode.
The foregoing objects, features and advantages of the present invention, will be discussed in detail in the following non-limiting description of specific embodiments in connection with the accompanying drawings.